What is the maximum stack height for road racing shoes?

World Athletics permits a maximum sole thickness of 40mm for road races. Track and field events are limited to 20mm. The measurement is taken at 12% and 75% of the shoe’s internal length, and the larger figure is used.

No. 04 — Legality

The rule is a line
40mm off the ground.

Shoes get called “banned” far more often than they are. The regulation that actually matters is a sole-thickness limit measured in millimetres — so here is the entire field, drawn to scale, standing against it.

All 42 shoes, ascending by measured stack · tap a bar for its sheet■ 9 exceed the road limit

Event

5K to marathon on the road, including all World Marathon Majors

Limit

40mm

Check a stack height

Every shoe v. road racing

Shoe	Stack	Verdict	Detail
adidas Prime X 3 Strung	50	over limit	50mm is 10.0mm over the 40mm limit for road racing, on the manufacturer's own figure.
HOKA Skyward X	49	over limit	49mm is 9.0mm over the 40mm limit for road racing, on the manufacturer's own figure.
HOKA Cielo X1 2.0	46	over limit	46mm is 6.0mm over the 40mm limit for road racing, on the manufacturer's own figure.
Brooks Hyperion Max 3	46	over limit	46mm is 6.0mm over the 40mm limit for road racing, on the manufacturer's own figure.
ASICS Superblast 3	45	over limit	45mm is 5.0mm over the 40mm limit for road racing, on the manufacturer's own figure.
ASICS Superblast 2	45	over limit	45mm is 5.0mm over the 40mm limit for road racing, on the manufacturer's own figure.
HOKA Skyward X 2	44	over limit	44mm is 4.0mm over the 40mm limit for road racing, on the manufacturer's own figure.
Saucony Kinvara Pro	42	over limit	42mm is 2.0mm over the 40mm limit for road racing, on the manufacturer's own figure.
New Balance FuelCell SuperComp Trainer v3	41	over limit	41mm is 1.0mm over the 40mm limit for road racing, on the manufacturer's own figure.
Nike Alphafly 3	40	inside the limit	40mm is exactly on the 40mm limit — too close to call from a stated figure.
Nike Zoom Fly 6	40	inside the limit	40mm is exactly on the 40mm limit — too close to call from a stated figure.
Saucony Endorphin Pro 4	40	inside the limit	40mm is exactly on the 40mm limit — too close to call from a stated figure.
New Balance FuelCell SC Elite v5	40	inside the limit	40mm is exactly on the 40mm limit — too close to call from a stated figure.
PUMA Fast-R Nitro Elite 3	40	inside the limit	40mm is exactly on the 40mm limit — too close to call from a stated figure.
PUMA Deviate Nitro Elite 3	40	inside the limit	40mm is exactly on the 40mm limit — too close to call from a stated figure.
HOKA Rocket X 3	40	inside the limit	40mm is exactly on the 40mm limit — too close to call from a stated figure.
Brooks Hyperion Elite 5	40	inside the limit	40mm is exactly on the 40mm limit — too close to call from a stated figure.
New Balance FuelCell SuperComp Elite v4	40	inside the limit	40mm is exactly on the 40mm limit — too close to call from a stated figure.
Nike Vaporfly 3	40	inside the limit	40mm is exactly on the 40mm limit — too close to call from a stated figure.
On Cloudboom Max	40	inside the limit	40mm is exactly on the 40mm limit — too close to call from a stated figure.
ASICS Metaspeed Sky Tokyo	39.5	inside the limit	39.5mm is 0.5mm inside the 40mm limit, on the manufacturer's own figure.
ASICS Metaspeed Edge Tokyo	39.5	inside the limit	39.5mm is 0.5mm inside the 40mm limit, on the manufacturer's own figure.
ASICS Metaspeed Ray	39.5	inside the limit	39.5mm is 0.5mm inside the 40mm limit, on the manufacturer's own figure.
Saucony Endorphin Elite 3	39.5	inside the limit	39.5mm is 0.5mm inside the 40mm limit, on the manufacturer's own figure.
Saucony Endorphin Elite 2	39.5	inside the limit	39.5mm is 0.5mm inside the 40mm limit, on the manufacturer's own figure.
On Cloudboom Strike	39.5	inside the limit	39.5mm is 0.5mm inside the 40mm limit, on the manufacturer's own figure.
Mizuno Wave Rebellion Pro 3	39.5	inside the limit	39.5mm is 0.5mm inside the 40mm limit, on the manufacturer's own figure.
adidas Adizero Adios Pro 3	39.5	inside the limit	39.5mm is 0.5mm inside the 40mm limit, on the manufacturer's own figure.
ASICS Metaspeed Sky Paris	39.5	inside the limit	39.5mm is 0.5mm inside the 40mm limit, on the manufacturer's own figure.
Under Armour Velociti Elite 2	39.5	inside the limit	39.5mm is 0.5mm inside the 40mm limit, on the manufacturer's own figure.
adidas Adizero Adios Pro Evo 2	39	inside the limit	39mm is 1.0mm inside the 40mm limit, on the manufacturer's own figure.
adidas Adizero Adios Pro 4	39	inside the limit	39mm is 1.0mm inside the 40mm limit, on the manufacturer's own figure.
adidas Adizero Evo SL	38.5	inside the limit	38.5mm is 1.5mm inside the 40mm limit, on the manufacturer's own figure.
HOKA Cielo X1 3.0	38	inside the limit	38mm is 2.0mm inside the 40mm limit, on the manufacturer's own figure.
ASICS Magic Speed 5	37.5	inside the limit	37.5mm is 2.5mm inside the 40mm limit, on the manufacturer's own figure.
Mizuno Wave Rebellion Flash 3	37.5	inside the limit	37.5mm is 2.5mm inside the 40mm limit, on the manufacturer's own figure.
Saucony Endorphin Speed 5	36	inside the limit	36mm is 4.0mm inside the 40mm limit, on the manufacturer's own figure.
Nike Vaporfly 4	35	inside the limit	35mm is 5.0mm inside the 40mm limit, on the manufacturer's own figure.
New Balance FuelCell SuperComp Pacer v2	35	inside the limit	35mm is 5.0mm inside the 40mm limit, on the manufacturer's own figure.
New Balance FuelCell Rebel v5	35	inside the limit	35mm is 5.0mm inside the 40mm limit, on the manufacturer's own figure.
adidas Adizero Takumi Sen 11	32	inside the limit	32mm is 8.0mm inside the 40mm limit, on the manufacturer's own figure.
Nike Streakfly 2	27	inside the limit	27mm is 13.0mm inside the 40mm limit, on the manufacturer's own figure.

■ How to read these figures

World Athletics measures sole thickness on one sample size — EU 42, a men’s US 8.5 — and larger sizes are allowed to exceed the limit. The figures here are the manufacturers’ own stated stack heights, which are not that measurement and which independent lab testing regularly finds to be optimistic by a millimetre or two. Treat this as an indication, not a ruling: if you are racing where the rule is enforced, check the official World Athletics shoe list for your model.

Does the rule even apply to you?

These regulations govern "Applicable Competitions" — World Athletics series events, Olympic and World Championship competition, World Athletics Label road races, and any event where a record or ranking score may be set. Elite fields at the big city marathons are checked. Mass-participation entrants almost never are, and parkrun, club races and most local events apply no shoe rule at all. If you are chasing a Championship-qualifying time, an age-group record or a place in an elite/championship field, the limit binds you. If you are running for a personal best, it does not.

The single-plate rule

A competition shoe may contain no more than one rigid embedded plate or blade. It may be split into parts, but those parts must sit sequentially in a single plane and must not overlap or stack.

In practice no shoe sold by a major brand breaks it — brands design to the rule. Stack height is the constraint that actually catches shoes out, which is why it is the one this page measures.

All limits, by event

Event	Max sole	Applies to
Road racing	40mm	5K to marathon on the road, including all World Marathon Majors
Track events	20mm	All track distances including hurdles and steeplechase
Field events	20mm	Jumps and throws
Cross country (spiked shoes)	20mm	Spiked cross country shoes
Cross country (non-spiked)	40mm	Road-style shoes worn on a cross country course
Race walking	40mm	Treated the same as road events
Mountain and trail	no limit	No stack height restriction

Summarised from World Athletics Book C, C2.1A Athletic Shoe Regulations; unified limits effective 1 Nov 2024, continuing under the 1 Jan 2026 regulations. Last reviewed 2026-09-04. Always check your own event's rules — and the official WA approved-shoe list if you compete where it is enforced.